Re: [PATCH RFC 01/10] nfsd41: sunrpc: svc_tcp_recv_record()

["J. Bruce Fields" <bfields@fieldses.org>]

On Thu, Aug 20, 2009 at 03:34:19AM +0300, Benny Halevy wrote:
> From: Alexandros Batsakis <batsakis@netapp.com>
> 
> Factor functionality out of svc_tcp_recvfrom() to simplify routine

Thanks, applied.

--b.

> 
> Signed-off-by: Alexandros Batsakis <batsakis@netapp.com>
> Signed-off-by: Ricardo Labiaga <Ricardo.Labiaga@netapp.com>
> Signed-off-by: Benny Halevy <bhalevy@panasas.com>
> ---
>  net/sunrpc/svcsock.c |   79 ++++++++++++++++++++++++++++++++-----------------
>  1 files changed, 51 insertions(+), 28 deletions(-)
> 
> diff --git a/net/sunrpc/svcsock.c b/net/sunrpc/svcsock.c
> index 23128ee..5a5bc8b 100644
> --- a/net/sunrpc/svcsock.c
> +++ b/net/sunrpc/svcsock.c
> @@ -826,21 +826,15 @@ failed:
>  }
>  
>  /*
> - * Receive data from a TCP socket.
> + * Receive data.
> + * If we haven't gotten the record length yet, get the next four bytes.
> + * Otherwise try to gobble up as much as possible up to the complete
> + * record length.
>   */
> -static int svc_tcp_recvfrom(struct svc_rqst *rqstp)
> +static int svc_tcp_recv_record(struct svc_sock *svsk, struct svc_rqst *rqstp)
>  {
> -	struct svc_sock	*svsk =
> -		container_of(rqstp->rq_xprt, struct svc_sock, sk_xprt);
>  	struct svc_serv	*serv = svsk->sk_xprt.xpt_server;
> -	int		len;
> -	struct kvec *vec;
> -	int pnum, vlen;
> -
> -	dprintk("svc: tcp_recv %p data %d conn %d close %d\n",
> -		svsk, test_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags),
> -		test_bit(XPT_CONN, &svsk->sk_xprt.xpt_flags),
> -		test_bit(XPT_CLOSE, &svsk->sk_xprt.xpt_flags));
> +	int len;
>  
>  	if (test_and_clear_bit(XPT_CHNGBUF, &svsk->sk_xprt.xpt_flags))
>  		/* sndbuf needs to have room for one request
> @@ -861,10 +855,6 @@ static int svc_tcp_recvfrom(struct svc_rqst *rqstp)
>  
>  	clear_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags);
>  
> -	/* Receive data. If we haven't got the record length yet, get
> -	 * the next four bytes. Otherwise try to gobble up as much as
> -	 * possible up to the complete record length.
> -	 */
>  	if (svsk->sk_tcplen < sizeof(rpc_fraghdr)) {
>  		int		want = sizeof(rpc_fraghdr) - svsk->sk_tcplen;
>  		struct kvec	iov;
> @@ -879,7 +869,7 @@ static int svc_tcp_recvfrom(struct svc_rqst *rqstp)
>  			dprintk("svc: short recvfrom while reading record "
>  				"length (%d of %d)\n", len, want);
>  			svc_xprt_received(&svsk->sk_xprt);
> -			return -EAGAIN; /* record header not complete */
> +			goto err_again; /* record header not complete */
>  		}
>  
>  		svsk->sk_reclen = ntohl(svsk->sk_reclen);
> @@ -894,6 +884,7 @@ static int svc_tcp_recvfrom(struct svc_rqst *rqstp)
>  					"per record not supported\n");
>  			goto err_delete;
>  		}
> +
>  		svsk->sk_reclen &= RPC_FRAGMENT_SIZE_MASK;
>  		dprintk("svc: TCP record, %d bytes\n", svsk->sk_reclen);
>  		if (svsk->sk_reclen > serv->sv_max_mesg) {
> @@ -914,11 +905,45 @@ static int svc_tcp_recvfrom(struct svc_rqst *rqstp)
>  		dprintk("svc: incomplete TCP record (%d of %d)\n",
>  			len, svsk->sk_reclen);
>  		svc_xprt_received(&svsk->sk_xprt);
> -		return -EAGAIN;	/* record not complete */
> +		goto err_again;	/* record not complete */
>  	}
>  	len = svsk->sk_reclen;
>  	set_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags);
>  
> +	return len;
> + error:
> +	if (len == -EAGAIN) {
> +		dprintk("RPC: TCP recv_record got EAGAIN\n");
> +		svc_xprt_received(&svsk->sk_xprt);
> +	}
> +	return len;
> + err_delete:
> +	set_bit(XPT_CLOSE, &svsk->sk_xprt.xpt_flags);
> + err_again:
> +	return -EAGAIN;
> +}
> +
> +/*
> + * Receive data from a TCP socket.
> + */
> +static int svc_tcp_recvfrom(struct svc_rqst *rqstp)
> +{
> +	struct svc_sock	*svsk =
> +		container_of(rqstp->rq_xprt, struct svc_sock, sk_xprt);
> +	struct svc_serv	*serv = svsk->sk_xprt.xpt_server;
> +	int		len;
> +	struct kvec *vec;
> +	int pnum, vlen;
> +
> +	dprintk("svc: tcp_recv %p data %d conn %d close %d\n",
> +		svsk, test_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags),
> +		test_bit(XPT_CONN, &svsk->sk_xprt.xpt_flags),
> +		test_bit(XPT_CLOSE, &svsk->sk_xprt.xpt_flags));
> +
> +	len = svc_tcp_recv_record(svsk, rqstp);
> +	if (len < 0)
> +		goto error;
> +
>  	vec = rqstp->rq_vec;
>  	vec[0] = rqstp->rq_arg.head[0];
>  	vlen = PAGE_SIZE;
> @@ -934,7 +959,7 @@ static int svc_tcp_recvfrom(struct svc_rqst *rqstp)
>  	/* Now receive data */
>  	len = svc_recvfrom(rqstp, vec, pnum, len);
>  	if (len < 0)
> -		goto error;
> +		goto err_again;
>  
>  	dprintk("svc: TCP complete record (%d bytes)\n", len);
>  	rqstp->rq_arg.len = len;
> @@ -960,21 +985,19 @@ static int svc_tcp_recvfrom(struct svc_rqst *rqstp)
>  
>  	return len;
>  
> - err_delete:
> -	set_bit(XPT_CLOSE, &svsk->sk_xprt.xpt_flags);
> -	return -EAGAIN;
> -
> - error:
> +err_again:
>  	if (len == -EAGAIN) {
>  		dprintk("RPC: TCP recvfrom got EAGAIN\n");
>  		svc_xprt_received(&svsk->sk_xprt);
> -	} else {
> +		return len;
> +	}
> +error:
> +	if (len != -EAGAIN) {
>  		printk(KERN_NOTICE "%s: recvfrom returned errno %d\n",
>  		       svsk->sk_xprt.xpt_server->sv_name, -len);
> -		goto err_delete;
> +		set_bit(XPT_CLOSE, &svsk->sk_xprt.xpt_flags);
>  	}
> -
> -	return len;
> +	return -EAGAIN;
>  }
>  
>  /*
> -- 
> 1.6.4
>